Various types of object inspection devices and techniques are known for inspecting analyzing, examining or otherwise confirming that a given object (e.g., product) conforms to some particular criterion. Such devices may include, without limitation, metal detectors, x-ray machines, cameras, lasers, scales and checkweighers. Object inspection may also occur in a wide variety of industries such as, to name a few, the food, chemical, and pharmaceutical industries.
The use of weighing devices such as checkweighers to weigh moving objects would be familiar to one of skill in the art, and various checkweigher designs exist for this purpose. Generally speaking, however, a checkweigher may be described as a high speed weighing device for the in-motion weighing of objects as the objects travel along a conveyor. A checkweigher is typically installed to a conveyor line such that an in-feed conveyor is provided for delivering objects to the checkweigher and a discharge conveyor is provided to transport objects from the checkweigher to a downstream location. The checkweigher itself also typically employs a conveyor to transport objects one at a time across a scale (weigh pan), which is essentially a vertically deflectable mechanism operable to effect weighing of the moving objects.
Typically, checkweighers are used to determine whether objects being weighed are of an expected weight, or within some acceptable range around an expected weight. If the weight of an object is deemed acceptable by a checkweigher, the object is normally passed to a downstream location, where the object may be further processed, packaged, etc. If the weight of an object is deemed unacceptable by a checkweigher, the object may be rejected. The rejection of an object for being of an unacceptable weight may result in a number of actions, which would be familiar to those of skill in the art. For example, an identifier (e.g., bar code) associated with a rejected object may be linked to a rejected status indicator, which may be used to prohibit some downstream action (e.g., packaging, shipping).
Another consequence of an object being rejected by a checkweigher for having an improper weight or by another inspection device for some other reason, and the consequence of interest to the present invention, is the physical removal of a rejected object from a discharge conveyor or other location downstream of the rejecting inspection device. For example, a number of rejection devices are known that may be activated upon receipt of a signal from an inspection device to selectively remove a defective (e.g., off-weight) object from a line of objects that have passed by, through or over the inspection device. Such a rejection device may be comprised of, for example, a linear actuator coupled to a pusher or other object engaging element, although virtually any device adapted to remove an object from a moving line of conveyed objects may be employed in conjunction with the present invention.
As should be apparent, it is normally desired that any object rejected by an inspection device be prevented from entering the stream of commerce. Rather, such objects may be destroyed, emptied and refilled, etc. Preferably, rejected objects may be quarantined until they can be retrieved for final disposition, such as by segregating the rejected objects in a reject bin or other suitable container or location.
Unfortunately, known reject bins and other devices provided to receive and retain objects rejected by an inspection device are either not secure in nature or, may be secure in nature but provide no mechanism for tracking the retrieval and disposition of the rejected objects contained therein. Therefore, rejected objects residing in such a reject bin may be easily removed and/or may be removed without any evidence indicating when the objects were removed, by whom the objects were removed, or to where the objects were removed. It is therefore possible for such rejected objects to be misplaced or to be inadvertently returned to a group of similar objects of proper weight and/or to otherwise make their way to an end-user.
It would, therefore, be desirable to provide a device for receiving and securely retaining objects rejected upon inspection. Preferably, such a device would limit access to only those persons to whom access has been specifically granted. Such a device may also log or otherwise record each entry thereto. Such a device may also be equipped with means for detecting the number of rejected objects present therein and the number of rejected objects removed therefrom during a given entry/removal event. The reject bin interlock invention provides for a device and method of securing objects rejected by an inspection device and of ensuring the traceability of objects received thereby and removed therefrom.